Thermoplastic polymer composition comprising a hyperbranched polymer and articles made using said composition

ABSTRACT

The invention relates to thermoplastic compositions comprising a polymer matrix and an additive which modifies the rheological behaviour of the matrix in the molten state. The purpose of the invention is to provide a preferably non-reactive additive which can be dispersed in the matrix and which can be used to obtain a good compromise in terms of rheological properties/mechanical properties. According to the invention, the additive is a hyperbranched polymer which is functionalised by R&lt;2&gt; radicals, R&lt;2&gt; being a radical of the following type: substituted or non-substituted hydrocarbon, of the silicon type, linear or branched alkyl, aromatic, arylalkyl, alkylaryl or cycloaliphatic, which can comprise one or more unsaturations and/or one or more heteroatoms. Preferably, the composition does not contain hyperbranched polymers which produce therein a reduction in the molar mass of matrix M which is greater than or equal to 7% in relation to a sample composition which comprises matrix M but which does not contain hyperbranched polymer additive(s). Said mass measurement is taken preferably using a predetermined protocol P. The invention is suitable for moulding, extrusion, engineered plastics, wires and fibres.

The field of the invention is that of thermoplastic polymer compositionscomprising a thermoplastic polymer matrix and at least one additive formodifying the rheological behaviour.

For the purposes of the present specification, the term “polymer”denotes either a homopolymer or a copolymer.

Thermoplastic polymers are raw materials that may be converted bymoulding, injection-moulding, injection blow-moulding, extrusion,extrusion blow-moulding or spinning, especially into numerous articlessuch as expanded, extruded or moulded parts (for example for bodywork),yarns, fibres or films.

There are at least two major constraints in all these approaches forconverting thermoplastic polymer.

The first of these constraints is that the thermoplastic polymers usedmight be characterized, in the melt, by a viscosity or rheologicalbehaviour that is compatible with the abovementioned forming processes.These thermoplastic polymers must be fluid enough when in the melt to beable to be conveyed and handled easily and quickly in certain formingmachines.

The other constraint that falls on thermoplastic polymer compositions isassociated with the mechanical qualities they must have after havingbeen melted, formed and cured by cooling. These mechanical qualities areespecially the impact strength, the flexural modulus and the flexuralbreaking strength, inter alia.

Moreover, it is common practice, in order to improve the mechanicalproperties of thermoplastic polymers, to incorporate reinforcing fillers(fibres or yarns) therein, for example mineral, glass or carbon fillers,to form composite materials.

One of the technical problems posed with regard to these twoconstraints: rheological behaviour in the melt and mechanical propertiesof the formed product in solidified form, is that they are, inprinciple, antinomic.

Specifically, to reduce the melt viscosity, it is well known to selectthermoplastic polymers that have low molar masses. However, this gain interms of rheology is achieved at the expense of the mechanical qualitiesof the formed and cured polymer.

In an attempt to correct this, it is also common practice to incorporateinto thermoplastic polymer matrices various additives capable ofmodifying their rheological behaviour in the melt. These additives areall the more useful when the polymers comprise reinforcing fillers.

The dilemma with which one is confronted with these additives is thatthey must be both inert or non-reactive with the matrix, so as not toinduce profound changes in the chemical structure (for examplecrosslinking), while at the same time being dispersible in this matrixso as to give it the required functionalities, in a homogeneous manner.

Now, the first requirement of non-reactivity would rather tend towardsadditive molecules that are incompatible with those of the matrix,whereas the second requirement of dispersibility rather directs theperson skilled in the art towards additives whose structure iscompatible with that of the matrix.

Moreover, additives that modify the rheology must be capable ofimproving the ability of the thermoplastic polymer to be moulded,injected or extruded.

As regards the polyamides that are more particularly of interest in thecontext of the present invention, it has been proposed to usehyperbranched polymers, and especially hyperbranched copolyamides, asadditives for modifying the rheology in thermoplastic polyamidematrices.

French patent application no. 2 793 252 describes hyperbranchedcopolyamides (HBPAs), for example of the type containing carboxylic acidend groups, obtained by melt-copolycondensation of1,3,5-benzenetricarboxylic acid (BTC): core molecule of R¹—B″₃ type,with B″═COOH, of 5-aminoiosophthalic acid (AIPA): branching molecule ofA-R—B₂ type, with A═NH₂ and B═COOH and of ε-caprolactam (CL): spacer ofA′-R′—B′ type with A′═NH₂ and B′═COOH—).

Hyperbranched polymers generally range from a few nanometers to severaltens of nanometers in size.

These hyperbranched polymers may be functionalized especially with fattychains or hydrophobic and/or hydrophilic chains, for the purposes ofbeing used, for example, as agents for modifying the surface propertiesof linear or branched polymers, preferably polyamides. Thesefunctionalities may be provided on the hyperbranched polymer byincorporating in the melt-copolycondensation a chain-terminating monomerof R′″-A type.

In this state of the art, one of the essential objects of the presentinvention is to propose an additive for modifying the rheologicalbehaviour of thermoplastic polymers, which is:

-   -   capable of allowing the controlled modification of the        rheological properties of the thermoplastic composition, in        particular the melt viscosity (fluidization), and of doing so        without affecting the mechanical properties of the formed and        cured thermoplastic polymer (impact strength),    -   preferably not reactive with respect to the thermoplastic        matrix, advantageously made of polyamide, i.e. not capable of        resulting in changes to the chemical structure of the        thermoplastic matrix, reflected, for example, by reductions in        the molar mass of the matrix,    -   preferably readily dispersible in this matrix.

Another object of the invention is to provide a thermoplastic polymercomposition comprising a thermoplastic matrix and at least one additivechosen from modifiers of the rheological behaviour in the melt, suchthat the composition has a melt fluid index that is suitable formoulding and injection-moulding operations (total filling of the mould),without affecting the mechanical properties, and in particular theimpact strength.

Another object of the present invention is to provide a thermoplasticpolymer composition that is adapted to the various melt-formingtechniques: injection-moulding, injection blow-moulding, extrusionblow-moulding, film formation, extrusion and spinning, and moreoverhaving high mechanical strength and optionally good transparency (lowcrystallinity).

Another object of the invention is to provide a thermoplastic polymercomposition that has the rheological (in the melt) and mechanicalqualities that are required in the plastics conversion industry, withoutthe supplementation performed to improve these properties being tooexpensive and disrupting the other properties of the thermoplastics.

Another object of the invention is to provide a hyperbranched polymeradditive for modifying rheological behaviour which is capable ofmodifying the melt rheological behaviour of thermoplastic polymercompositions in a controlled and optimized manner.

Another essential object of the invention is to provide articlesobtained by conversion (mouldings, injection-moulding, injectionblow-moulding, extrusion blow-moulding, extrusion or spinning) of thecomposition as defined in the above objects.

These objects, inter alia, are achieved by the present invention, whichderive from the astute and advantageous selection that the inventors, totheir credit, have made, by selecting specific hyperbranched polymers asadditives for modifying the melt rheological behaviour.

Consequently, the present invention relates firstly to a thermoplasticpolymer composition, characterized in that it comprises:

-   -   a matrix M based on at least one thermoplastic polymer,    -   and at least one hyperbranched polymer additive for modifying        the rheological behaviour, comprising at least one polymer:        -   which is functionalized,        -   which is hyperbranched,        -   at least 50% of the end groups of this hyperbranched polymer            are functionalized with R²,        -   R² being a substituted or unsubstituted hydrocarbon-based            radical of the silicone, linear or branched alkyl, aromatic,            arylalkyl, alkylaryl or cycloaliphatic type which may            comprise one or more unsaturations and/or one or more hetero            atoms.

The expression “hyperbranched polymer” means a branched polymerstructure obtained by polymerization in the presence of compounds havinga functionality of greater than 2, and the structure of which is notfully controlled. They are often random copolymers. Hyperbranchedpolymers may be obtained, for example, by reaction especially betweenmultifunctional monomers, for example, trifunctional and bifunctionalmonomers, each of the monomers bearing at least two differentpolymerization-reactive functions.

Advantageously, the hyperbranched polymer of the invention is chosenfrom hyperbranched polyesters, polyesteramides and polyamides.

The hyperbranched polymer additive of the invention is preferably ahyperbranched polyamide comprising at least one hyperbranchedcopolyamide of the type obtained by reaction between:

-   -   at least one monomer of formula (I) below:        A-R—B_(f)  (I)    -    in which A is a polymerization-reactive function of a first        type, B is a polymerization-reactive function of a second type        that is capable of reacting with A, R is a hydrocarbon-based        species optionally comprising hetero atoms, and f is the total        number of reactive functions B per monomer: f≧2, preferably        2≦f≦10;    -   optionally at least one difunctional spacer monomer of        formula (II) below:        A′-R′—B′ or the corresponding lactams,  (II)    -    in which A′, B′ and R′ have the same meaning as that given        above for A, B and R, respectively in formula (I);    -   optionally at least one “core” monomer of formula (III):        R¹(B″)_(n)  (III)    -    in which:        -   R¹ is a substituted or unsubstituted hydrocarbon-based            radical of the silicone, linear or branched alkyl, aromatic,            alkylaryl, arylalkyl or cycloaliphatic type which may            comprise unsaturations and/or hetero atoms;        -   B″ is a reactive function of the same nature as B or B′;        -   n≧1, preferably 1≦n≦100; and    -   at least one “chain-limiting” functionalization monomer        corresponding to formula (IV):        R²-A″  (IV)    -    in which:        -   A″ is a reactive function of the same nature as A or A′.

Preferably, the composition according to the invention is free ofhyperbranched polymer additives, resulting in a reduction of the molarmass of the matrix M of greater than or equal to 7% relative to acontrol composition comprising the same matrix M not supplemented withhyperbranched polymer, the molar mass measurement being performedaccording to a given protocol P. The details of protocol P for measuringthe molar mass are given in the examples below.

In accordance with the invention, the functionalized hyperbranchedpolymer additive thus advantageously has the characteristic of beingable to modify the rheological behaviour of a thermoplastic polymermatrix, without affecting its structural integrity, and in particularwithout consequently decreasing its molar mass. This means that theadditive does not appear to react with the matrix.

According to the present invention, the molar mass is defined as themaximum of the distribution of the molar masses of the polymer matrixsupplemented with functionalized hyperbranched polymer, in polystyreneequivalents, by Gel Permeation Chromatography (GPC), with detection byrefractometry, as is defined in protocol P given in detail below.

The molar mass measurement is performed on the composition to beanalysed and on the control composition, which are extruded, solidifiedand then optionally formed into granules.

The abovementioned protocol P for measuring the molar mass of the matrixM in a composition to be analysed and in a control composition involvesan extrusion, which leads to the production of rods. The rods (placedbeforehand in the form of granules) are then subjected to the actualmolar mass determination. This protocol P for measuring the molar massof the compositions according to the invention and of the controlcompositions is as follows:

1. Matrix M/Functionalized Hyperbranched Polymer Compositions

The matrix M, especially polyamide and the functionalized hyperbranchedpolymer are in ground or crushed form as powder, flakes or granules, andare then preblended.

The blend is introduced into a twin-screw extruder. This mixture ismelted in the extruder at a temperature Q which is about 30° C. higherthan the melting point Q_(melting) of the matrix M.

Homogenization of M/hyperbranched polymer is thus performed for 5minutes and rods are collected at the extruder outlet, and then placedin the form of granules.

The actual molar mass measurement is performed on the granules by gelpermeation chromatography (GPC) in dicholoromethane after derivatizationof the polyamide with trifluoroacetic anhydride, relative to polystyrenestandards. The detection technique used is refractometry.

2/ Control Compositions of Matrix M without Hyperbranched PolymerAdditive

For each given M/hyperbranched polymer composition, a molar massmeasurement of the same matrix M is performed on a compositioncomprising the matrix M without hyperbranched polymer additive.

The method is performed on granules of polymer M, especially ofpolyamide obtained in the same way as that indicated in point 1 above,the only difference being that the granules do not contain anyhyperbranched polymer additive.

As regards the composition M+functionalized hyperbranched polymer of theinvention, it may be noted that extrusion constitutes one means, amongothers, for melt-blending the constituents M and functionalizedhyperbranched polymer.

The radical R² for functionalization of the hyperbranched polymer ispreferably not reactive with the matrix and, entirely surprisingly andunexpectedly, induces a quite significant fluidization of thecomposition in the melt. Specifically, the gains obtained in thisrespect are particularly large since they may be, for example, at least10 to 50%, without this adversely affecting the mechanical properties,and in particular the impact strength of the thermoplastic.

The flow index/impact strength compromise achieved is entirelyadvantageous.

The functionalized hyperbranched polymer additive used in accordancewith the invention is easy to use and economical.

According to one preferred arrangement of the invention, thefunctionalized hyperbranched polyamide additive of the composition ischaracterized in that:

-   -   the hydrocarbon-based species R and R′ of the monomers (I)        and (II) respectively, each comprise:    -   i. at least one linear or branched aliphatic radical;    -   ii. and/or at least one cycloaliphatic radical;    -   iii. and/or at least one aromatic radical comprising one or more        aromatic nuclei;    -   iv. and/or at least one arylaliphatic radical;        -   these radicals (i), (ii), (iii) and (iv) possibly being            substituted and/or comprising hetero atoms;    -   A or A′ is a reactive function of the amine or amine salt type        or of the acid, ester, acid halide or amide type;    -   B or B′ is a reactive function of the acid, ester, acid halide        or amide type or of the amine or amine salt type.

Thus, the polymerization-reactive functions A, B, A′ and B′ that aremore especially selected are those belonging to the group comprisingcarboxylic and amine functions.

For the purposes of the invention, the term “carboxylic function” meansany acid function COOH or derivative of the ester, acid halide(chloride), or anhydride type.

Advantageously, the hyperbranched polyamide for modifying therheological behaviour in the composition may consist of a mixture ofseveral different monomers (I), several different monomers (II) and/orseveral different functionalization monomers (IV).

The difunctional monomers (II) are spacer elements in thethree-dimensional structure.

According to one advantageous embodiment of the invention, the spacermonomers (II), the chain-limiting monomers (IV) and/or the monomers(III) of “core” type may be in the form of oligomers.

Preferably, f=2, such that the monomer (I) is trifunctional: A-R—B₂,A=amine function, B=carboxylic function and R=aromatic radical.

Moreover, it is preferable for the functionalized hyperbranchedpolyamide additive to be characterized by a molar ratio III/I+II+IVdefined as follows:

-   -   III/I+II+IV≦1/150    -   and preferably III/I+II+IV≦1/100    -   and even more preferably III/I+II+IV≦1/50.

According to one particular feature of the invention, the functionalizedhyperbranched polyamide additive used is, for example:

-   -   either “small” (of low mass), i.e. characterized by a ratio:        -   1/10≦III/I+II+IV≦1/40,    -   or “large” (of high mass), i.e. characterized by a ratio:        -   1/50≦III/I+II+IV≦1/90.

According to one advantageous variant, the radical R² forfunctionalization of the hyperbranched polymer is chosen from linearalkyls containing from 8 to 30 carbon atoms and preferably from 10 to 20carbon atoms, or polycondensed or non-polycondensed aryls, arylalkyls oralkylaryls.

In practice, and without it being limiting for the functionalizedhyperbranched polyamide:

-   -   the monomer (I) is chosen from the group comprising:        -   5-amino-isophthalic acid,        -   6-amino-undecanedioic acid,        -   3-aminopimelic diacid,        -   aspartic acid,        -   3,5-diaminobenzoic acid,        -   3,4-diaminobenzoic acid,        -   and mixtures thereof;    -   the difunctional monomer of formula (II) is chosen from the        group comprising:        -   ε-caprolactam and/or the corresponding amino acid;            aminocaproic acid,        -   para- or meta-aminobenzoic acid,        -   11-amino-undecanoic acid,        -   lauryllactam and/or the corresponding amino acid,        -   12-aminododecanoic acid,        -   and mixtures thereof;    -   the “core” monomer (III) is chosen from the group comprising:        -   1,3,5-benzenetricarboxylic acid,        -   2,2,6,6-tetra(β-carboxyethyl)cyclohexanone,        -   2,4,6-(triaminocaproic acid)-1,3,5-triazine,        -   4-aminoethyl-1,8-octanediamine,        -   and mixtures thereof;    -   the “chain-limiting” functionalization monomer (IV) is chosen        from the group comprising:        -   n-hexadecylamine,        -   n-octadecylamine,        -   n-dodecylamine,        -   benzylamine,        -   and mixtures thereof.

For further details regarding this hyperbranched polyamide, referencewill be made to French patent application No 2 793 252, both as regardsthe structural aspects and as regards the methods for obtaining thisfunctionalized hyperbranched polyamide.

As regards the monomers (I), (II) and optionally (III), mention will bemade, respectively, of 5-aminoisophthalic acid (AIPA, branching moleculeof A-R′—B₂ type, with A═NH₂), caprolactam (written CL, spacer of A-R″—Btype) and 1,3,5-benzenetricarboxylic acid (BTC, core molecule of R—B3type, with B═COOH).

In quantitative terms, it is preferable within the context of theinvention for the additive comprising the hyperbranched copolymer to bepresent in a proportion (as a % of the dry weight relative to the totalmass of the composition) of:

-   -   0.1 to 50    -   preferably 1 to 20    -   and even more preferably 2 to 10.

Furthermore, it has been found to be particularly advantageous for thehyperbranched polyamide functionalized and used as additive formodifying the rheological behaviour in the composition according to theinvention to be a hyperbranched polyamide whose content of acid or amineend groups (EG) (expressed in meq/kg) is between 0 and 100, preferablybetween 0 and 50 and even more preferably between 0 and 25.

According to one particular embodiment of the invention, thefunctionalization radicals R² of the hyperbranched polymer are of thesame type throughout the hyperbranched polymer. For example, thehyperbranched polymer may comprise radicals. R² solely of alkyl type,rather than a mixture of several types of radicals R².

The manufacture of a functionalized hyperbranched copolyamide of thetype targeted above, namely:

-   -   consisting of one or more functionalized arborescent structures,        via monomers (IV) bearing the functionality or functionalities        under consideration, and    -   of the type such as the copolyamides obtained by reaction        between:        -   at least one monomer of formula (I) below:            A-R—B_(f)  (I)        -    in which A is a polymerization-reactive function of a first            type, B is a polymerization-reactive function of a second            type capable of reacting with A, R is a hydrocarbon-based            species optionally comprising hetero atoms, and f is the            total number of reactive functions B per monomer: f≧2,            preferably 2≦f≦10;        -   optionally at least one difunctional monomer of formula (II)            below:            A′-R′—B′ or the corresponding lactams,  (II)        -    in which A′, B′ and R′ have the same meaning as those given            above for A, B, and R, respectively in formula (I);        -   optionally at least one “core” monomer of formula (III);            R¹(B″)_(n)  (III)        -    in which:        -   R¹ is a substituted or unsubstituted hydrocarbon-based            radical, of the silicone, linear or branched alkyl,            aromatic, alkylaryl, arylalkyl or cycloaliphatic type which            may comprise unsaturations and/or hetero atoms;            -   B″ is a reactive function of the same nature as B or B′;            -   n≧1, preferably 1≦n≦100        -   and at least one “chain-limiting” functionalization monomer            corresponding to formula (IV):            R²-A″  (IV)        -    in which:        -   R² is a substituted or unsubstituted hydrocarbon-based            radical, of the silicone, linear or branched alkyl,            aromatic, arylalkyl, alkylaryl or cycloaliphatic type which            may comprise one or more unsaturations and/or one or more            hetero atoms,        -   and A″ is a reactive function of the same nature as A or A′;            is performed by melt-polycondensation between monomers (I),            possibly monomers (II), which also react together and with            monomers (IV), and possibly with monomers (III).

The polymerization by copolycondensation is carried out, for example,under conditions and according to a procedure that are equivalent tothose used for the manufacture of linear polyamides, for examplestarting with monomers (II).

As regards the constituent that is essential, in quantitative terms, ofthe composition according to the invention, namely the thermoplasticmatrix, the thermoplastic (co)polymer(s) constituting the matrix is(are) chosen from the group comprising:

polyolefins, polyesters, polyalkylene oxides, polyoxyalkylenes,polyhalogenoalkylenes, poly(alkylenephthalates or terephthalates),poly(phenyl or phenylenes), poly(phenylene oxide or sulphide), polyvinylacetates, polyvinyl alcohols, polyvinyl halides, polyvinylidene halides,polyvinyl nitrites, polyamides, polyimides, polycarbonates,polysiloxanes, acrylic or methacrylic acid polymers, polyacrylates orpolymethacrylates, natural polymers, namely cellulose and itsderivatives, synthetic polymers such as synthetic elastomers, orthermoplastic copolymers comprising at least one monomer that isidentical to any of the monomers included in the abovementionedpolymers, and also blends and/or alloys of all these co(polymers).

In specific terms, it may be mentioned that the matrix may consist of atleast one of the following polymers or copolymers:

polyacrylamide, polyacrylonitrile, poly(acrylic acid), ethylene-acrylicacid copolymers, ethylene-vinyl alcohol copolymers, methylmethacrylate-styrene copolymers, ethylene-ethyl acrylate copolymers,(meth)acrylate-butadiene-styrene (ABS) copolymers, and polymers of thesame family; polyolefines, for instance low density poly(ethylene),poly(propylene), low-density chlorinated poly(ethylene),poly(4-methyl-1-pentene), poly(ethylene), poly(styrene), and polymers ofthe same family; ionomers: poly(epichlorohydrins); poly(urethanes) suchas products of polymerization of diols, for instance glycerol,trimethylolpropane, 1,2,6-hexanetriol, sorbitol, pentaerythritol,polyetherpolyols, polyesterpolyols and compounds of the same family withpolyisocyanates, for instance 2,4-tolylene diisocyanate, 2,6-tolylenediisocyanate, 4,4′-diphenylmethane diisocyanate, 1,6-hexamethylenediisocyanate, 4,4′-dicyclohexylmethane diisocyanate and compounds of thesame family; and polysulphones such as the products of reaction betweena sodium salt of 2,2-bis(4-hydroxyphenyl)propane and4,4′-dichlorodiphenyl sulphone; furan resins, for instance, poly(furan);cellulose-ester plastics, for instance cellulose acetate,cellulose-acetate-butyrate, cellulose propionate and polymers of thesame family; silicones, for instance poly(dimethylsiloxane),poly(dimethylsiloxane co-phenylmethylsiloxane), and polymers of the samefamily; blends of at least two of the above polymers.

Advantageously, the thermoplastic polymer matrix M is made of polyester,such as polyethylene terephthalate (PET), polypropylene terephthalate(PPT), or polybutylene terephthalate (PBT), and copolymers and blendsthereof.

The thermoplastic polymer(s) is (are) even more preferably selected fromthe group of (co)polyamides comprising: nylon 6, nylon 6,6, nylon 4,nylon 11, nylon 12, polyamides 4-6, 6-10, 6-12, 6-36 and 12-12, andcopolymers and blends thereof.

Other preferred polymers of the invention that may be mentioned includesemicrystalline or amorphous polyamides, such as aliphatic polyamides,semi-aromatic polyamides and more generally the linear polyamidesobtained by polycondensation between a saturated aliphatic or aromaticdiacid and a saturated aromatic or aliphatic primary diamine, thepolyamides obtained by condensation of a lactam, an amino acid or thelinear polyamides obtained by condensation of a blend of these variousmonomers.

More specifically, these copolyamides may be, for example,polyhexamethyleneadipamide, the polyphthalamides obtained fromterephthalic acid and/or isophthalic acid, such as the polyamide soldunder the trade name Amodel, and the copolyamides obtained from adipicacid, from hexamethylene diamine and from caprolactam.

In accordance with one preferred embodiment of the invention, thethermoplastic (co)polymer(s) is (are) a polyamide 6,6.

According to one particular embodiment of the invention, thethermoplastic polymer(s) is (are) a polyamide 6, whose relativeviscosity, measured at 25° C. at a concentration of 0.01 g/ml in 96%sulphuric acid solution, is greater than 3.5 and preferably greater than3.8.

According to another advantageous characteristic of the invention, thepolymer matrix (M) of the composition consists of a blend and/or alloyof a polyamide with one or more other polymers, preferably polyamides orcopolyamides.

A blend and/or alloy of (co)polyamide with at least one polymer of thepolypropylene oxide (PPO), polyvinyl chloride (PVC), orpolyacrylo-butadiene-styrene (ABS) type, may also be envisaged.

To improve the mechanical properties of the composition according to theinvention, it may be advantageous to incorporate therein at least onereinforcing filler and/or bulking filler chosen from the groupcomprising fibrous fillers such as glass fibres, mineral fillers, suchas clays, kaolin, reinforcing nanoparticles or particles made ofthermosetting material, and powder fillers such as talc.

The degree of incorporation of reinforcing filler is in accordance withthe standards in the field of composite materials. It may be, forexample, a filler content of 1% to 90%, preferably of 10% to 60% andmore specifically 50%.

The hyperbranched polymer additives may also be combined with otherreinforcing additives such as resilience modifiers, for instanceoptionally grafted elastomers.

Naturally, the composition according to the invention may also containany other suitable additives or adjuvants, for example bulking fillers(SiO₂), flame retardants, UV stabilizers, heat stabilizers, mattingagents (TiO₂), lubricants, plasticizers, compounds that are useful forcatalysing the synthesis of polymer matrix, antioxidants, antistaticagents, pigments, colorants, moulding aids or surfactants. This list isnot in any way limiting.

The compositions according to the invention may be used as raw materialsin the field of technical plastics, for example for producing articlesmoulded by injection-moulding or by injection blow-moulding, extruded bystandard extrusion or by blow-extrusion, or films.

The compositions according to the invention may also be made in the formof yarns, fibres or filaments by melt spinning.

The functionalized hyperbranched polymer additive of the invention isintroduced into the thermoplastic polymer matrix, preferably polyamide.To do this, use may be made of any known methods for introducingparticles into a matrix.

A first method might consist in blending the functionalizedhyperbranched polymer into the molten matrix, and optionally insubjecting the blend to a high shear, for example in a twin-screwextrusion device, so as to produce a good dispersion. Such a device isgenerally arranged upstream of the means for forming the plastic melt(moulding, extrusion or spinning). According to one common embodiment,this blend is extruded in the form of rods that are then chopped intogranules. The moulded parts are then produced by melting the granulesproduced above and feeding the composition in the melt into suitablemoulding, injection, extrusion or spinning devices.

In the case of manufacturing yarns, fibres and filaments, thecomposition obtained at the extruder outlet optionally directly feeds aspinning plant.

A second method may be that which consists in blending the hyperbranchedpolymer with monomers, in the polymerization medium of the thermoplasticmatrix or during the polymerization.

According to one variant, a concentrated blend of a resin and offunctionalized hyperbranched polymer, prepared, for example, accordingto one of the methods described previously, may be blended with thematrix melt.

According to another of its aspects, the present invention is directedtowards the articles obtained by forming, preferably by moulding,injection-moulding, injection blow-moulding, extrusion, extrusionblow-moulding or spinning, one of the polymer compositions to whichhyperbranched polymer has been added and as defined above.

These articles may be yarns, fibres, films or filaments.

They may also be articles moulded using the composition according to theinvention comprising a polymer, especially a polyamide, hyperbranchedpolymer as defined above, and optionally reinforcing fibres (glass).

A subject of the invention is also the use, as an agent for modifyingthe rheological behaviour of a thermoplastic polymer matrix, of thefunctionalized hyperbranched polymer as defined above.

Other details and advantages of the invention will emerge more clearlyin the light of the examples given below, purely for the purposes ofillustration.

EXAMPLES Example 1 to 6 Synthesis of Hyperbranched Polyamide (HBPA)Based on BTC/AIPA/CL/C₁₆ or C₁₈ Alkyl (Examples 5 and 6) Example 7Characterization of the HBPAs of Examples 1 to 4 and 6 Example 8Preparation of Compositions According to the Invention Based onPolyamide PA 6,6, on Glass Fibres and on Alkyl HBPAs According toExamples 1 to 3, at Various Degrees of Incorporation Example 9Preparation of Composition According to the Invention without GlassFibre Based on PA 6,6, HBPA of Examples 1 and 2 According to Two Degreesof Incorporation Example 10 Preparation of Compositions According to theInvention Based on PA 6 and HBPA of Example 6 Example 11 Preparation ofCompositions According to the Invention Based on High-Mass PA 6 and HBPAof Example 6 Example 12 Preparation of Compositions According to theInvention Based on Polypropylene and HBPA of Example 6 Example 13Preparation of Compositions According to the Invention Based on PA 6,6and on Functionalized Hyperbranched Products Boltorn® (Perstorp) Example14 Evaluation of the Rheological and Mechanical Characteristics of theCompositions of Example 8 and 9 Example 15 Evaluation of the Flow Indexof the Compositions of Examples 10 and 11 Example 16 Evaluation of theFlow Index of the Compositions of Examples 12 Example 17 Evaluation ofthe Flow Index of the Compositions of Example 13 Example 18 Measurementof the Values of the Reductions in Pack Pressure (Die Head) during theSpinning of the M/Functionalized HBPA Compositions of Examples 2 and 4Example 19 Measurement of the Reductions in Pack Pressure (Die Head)during the Spinning of Compositions Based on High-Mass PA 6 and HBPA ofExample 6 DESCRIPTION OF THE FIGURES

The attached FIG. 1 is a histogram of the variation in the gain ofspiral length for the compositions PA 6,6+50% glass fibre+HBPA/C₁₆ ofTable II.

FIG. 2 is a histogram of the gains in spiral length for the compositionsPA 6,6+HBPA/C₁₆ of Table III.

FIG. 3 takes into account the flow index/impact strength compromise bygiving the impact strength as a function of the spiral length for thecompositions of Table II. The key to FIG. 3 is as follows:

♦: Control PA 6,6+50% GF;

□: PA 6,6+50% GF+2% HBPA/C₁₆ Ex. 1;

▪: PA 6,6+50% GF+5% HBPA/C₁₆ Ex. 1;

◯: PA 6,6+50% GF+2% HBPA/C₁₆ Ex. 2;

●: PA 6,6+50% GF+5% HBPA/C₁₆ Ex. 2;

Δ: PA 6,6+50% GF+2% HBPA/C₁₆ Ex. 3;

▴: PA 6,6+50% GF+5% HBPA/C₁₆ Ex. 3;

Example 1

synthesis of a hyperbranched copolyamide containing hexadecylamide endgroups by melt-copolycondensation of 1,3,5-benzenetricarboxylic acid(written BTC, core molecule of R¹—B₃ type, with B═COOH) of5-aminoisophthalic acid (written AIPA, branching molecule of A-R—B₂type, with A═NH₂), of ε-caprolactam (written CL, spacer of A-R′—B type)and of n-hexadecylamine (written C₁₆, alkyl blocker of R²-A type). Therespective overall composition is 1/25/25/28 of BTC/AIPA/CL/C₁₆,(III/I+II+IV=1/78)

The reaction is performed at atmospheric pressure in a 7.5 l autoclavecommonly used for the molten-phase synthesis of polyesters orpolyamides.

The monomers are completely loaded at the start of the test into thereactor preheated to 70° C. and with stirring at 80 rpm. 1685.0 g ofmolten 90% pure hexadecylamine (6.28 mol), 634.6 g of α-caprolactam(5.61 mol), 1015.8 g of 5-aminoisophthalic acid (5.61 mol), 47.1 g of1,3,5-benzenetricarboxylic acid (0.22 mol) and 6.0 g of aqueous 50%(w/w) hypophosphorous acid are successively introduced into the reactor.The reactor is purged by a succession of 4 sequences of placing undervacuum and re-establishing the atmospheric pressure with dry nitrogen.

The reaction mass is gradually heated from 70 to 260° C. with stirring,over about 200 minutes.

After stirring for 30 minutes at 260° C., the reactor is graduallyplaced under vacuum over 60 minutes. The minimum vacuum is thenmaintained for a further 30 minutes. 229.5 g of distillate arerecovered.

At the end of the cycle, the stirring is stopped and the reactor isplaced under an excess pressure of nitrogen. Next, the base valve isgradually opened and the polymer is run out at 260° C. into astainless-steel bucket. The product is then cooled in cardice under astream of nitrogen. 2900 g of polymer are collected.

The hyperbranched copolyamide obtained is vitreous and may be readilycrushed into flakes or ground.

Example 2

synthesis of a hyperbranched copolyamide containing hexadecylamide endgroups by melt-copolycondensation of 1,3,5-benzenetricarboxylic acid(written BTC, core molecule of R¹—B₃ type, with B═COOH) of5-aminoisophthalic acid (written AIPA, branching molecule of A-R—B₂type, with A═NH₂), of ε-caprolactam (written CL, spacer of A-R′—B type)and of n-hexadecylamine (written C₁₆, alkyl blocker of R²-A type). Therespective overall composition is 1/6/6/9 of BTC/AIPA/CL/C₁₆,(III/I+II+IV=1/21) The assembly and procedure used are identical in allrespects to those described in Example 1.

1867.4 g of molten 90% pure hexadecylamine (6.96 mol), 525.1 g ofε-caprolactam (4.64 mol), 840.6 g of 5-aminoisophthalic acid (4.64 mol),162.5 g of 1,3,5-benzenetricarboxylic acid (0.77 mol), and 6.1 g ofaqueous 50% (w/w/) hypophosphorous acid solution are successively loadedinto the reactor preheated to 70° C.

The reaction mass is gradually heated from 70 to 260° C. with stirring,over about 200 minutes.

After stirring for 30 minutes at 260° C., the reactor is placed undervacuum to complete the polycondensation. 155.2 g of distillate arecollected.

At the end of the cycle, the polymer is discharged via the base valve at260° C. into a stainless-steel beaker and then cooled in cardice under astream of nitrogen. 2946 g of polymer are collected.

The hyperbranched copolyamide obtained is vitreous.

Example 3

synthesis of a hyperbranched copolyamide containing hexadecylamide endgroups by melt-copolycondensation of 1,3,5-benzenetricarboxylic acid(written BTC, core molecule of R¹—B₃ type, with B═COOH) of5-aminoisophthalic acid (written AIPA, branching molecule of A-R—B₂type, with A═NH₂), of ε-caprolactam (written CL, spacer of A-R′—B type)and of n-hexadecylamine (written C₁₆, alkyl blocker of R²-A type). Therespective overall composition is 1/20/40/23 of BTC/AIPA/CL/C₁₆,(III/I+II+IV=1/83)

The assembly and the procedure used are identical in all respects tothose described in Example 1.

1408.9 g of molten 90% pure hexadecylamine (5.25 mol), 1033.5 g ofε-caprolactam (9.13 mol), 827.2 g of 5-aminoisophthalic acid (4.57 mol),48.0 g of 1,3,5-benzenetricarboxylic acid (0.23 mol) and 6.5 g ofaqueous 50% (w/w) hypophosphorous acid solution are successively loadedinto the reactor preheated to 70° C.

The reactor is stirred and heated as in Example 1. 193.4 g of distillateare collected.

At the end of the cycle, the polymer is run into a stainless-steelbeaker and then cooled in cardice under a stream of nitrogen. 2837.5 gof polymer are collected.

The hyperbranched copolyamide obtained is vitreous.

Example 4

synthesis of a hyperbranched copolyamide containing hexadecylamide endgroups by melt-copolycondensation of 1,3,5-benzenetricarboxylic acid(written BTC, core molecule of R¹—B₃ type, with B═COOH) of5-aminoisophthalic acid (written AIPA, branching molecule of A-R—B₂type, with A═NH₂), of ε-caprolactam (written CL, spacer of A-R′—B type)and of n-hexadecylamine (written C₁₆, alkyl blocker of R²-A type). Therespective overall composition is 1/5/10/8 of BTC/AIPA/CL/C₁₆,(III/I+II+IV=1/23)

The reaction is carried out at atmospheric pressure in a 1.0 l autoclavecommonly used in the laboratory for the molten-phase synthesis ofpolyesters or polyamides.

The monomers are completely loaded at the start of the test into thereactor at 20° C. 190.4 g of solid 90% pure hexadecylamine (0.71 mol),100.4 g of ε-caprolactam (0.89 mol), 80.4 g of 5-aminoisophthalic acid(0.44 mol), 18.6 g of 1,3,5-benzenetricarboxylic acid (0.09 mol) and0.76 g of aqueous 50% (w/w) hypophosphorous acid solution aresuccessively loaded into the reactor.

The reaction mass is gradually heated from 20 to 260° C. with stirring,over about 200 minutes.

After stirring for 63 minutes at 260° C., the reactor is graduallyplaced under vacuum over 61 minutes. The minimum vacuum achieved is 1 to2 mbar and is then maintained for a further 30 minutes. About 8 ml ofdistillate are collected.

At the end of the cycle, the stirring is stopped and the reactor isplaced under an excess pressure of nitrogen. The base valve is graduallyopened and the polymer is run out into a stainless-steel beaker. Theproduct is then cooled in cardice under a stream of nitrogen. 339 g ofpolymer are collected, including the samples taken during synthesis.

The hyperbranched copolyamide obtained is vitreous.

Example 5

synthesis of a hyperbranched copolyamide containing octadecylamide endgroups by melt-copolycondensation of 1,3,5-benzenetricarboxylic acid(written BTC, core molecule of R¹—B₃ type, with B═COOH) of5-aminoisophthalic acid (written AIPA, branching molecule of A-R—B₂type, with A═NH₂), of C-caprolactam (written CL, spacer of A-R′—B type)and of n-octadecylamine (written C₁₈, alkyl blocker of R²-A type). Therespective overall composition is 1/6/6/9 of BTC/AIPA/CL/C₁₈,(III/I+II+IV=1/21)

The reaction is performed at atmospheric pressure in a 0.5 l glassautoclave commonly used in the laboratory for the molten-phase synthesisof polyesters or polyamides.

122.0 g of 90% pure octadecylamine pellets (0.41 mol), 30.9 g ofε-caprolactam (0.27 mol), 49.4 g of 5-aminoisophthalic acid (0.27 mol),9.6 g of 1,3,5-benzenetricarboxylic acid (0.05 mol) and 0.25 g ofaqueous 50% (w/w) hypophosphorous acid solution are successively loadedinto the reactor at 90° C.

The reaction mass is gradually heated from 90 to 260°c with stirring,over about 200 minutes.

The temperature is maintained at 260° C. with stirring for 60 minutes.The reactor is then gradually placed under vacuum over 38 minutes. Theminimum vacuum reached is 5 mbar and is then maintained for a further 65minutes. 12.5 g of distillate are collected.

At the end of the cycle, the polymer is cooled in the reactor under astream of nitrogen. 157.9 g of polymer are collected (without takinginto account the samples removed during synthesis). The hyperbranchedcopolyamide is vitreous and may be readily crushed into flakes orground.

Example 6

synthesis of a hyperbranched copolyamide containing hexadecylamide endgroups by melt-copolycondensation of 1,3,5-benzenetricarboxylic acid(written ARC, core molecule of R¹—B₃ type, with B=COOH) of5-aminoisophthalic acid (written AIPA, branching molecule of A-R—B₂type, with A═NH₂), of ε-caprolactam (written CL, spacer of A-R′—B type)and of n-octadecylamine (written C₁₈, alkyl blocker of R²-A type). Therespective overall composition is 1/6/6/9 of BTC/AIPA/CL/C₁₈,(III/I+II+IV=1/21)

The reaction is performed at atmospheric pressure in a 200 l autoclavecommonly used for the molten-phase synthesis of polyesters orpolyamides.

The monomers are completely loaded at the start of the test into thereactor preheated to 70° C. and with stirring at 80 rpm. 47 kg of moltenoctadecylamine (0.17 mol), 14.0 kg ε-caprolactam (0.12 mol), 22.4 kg of5-aminoisophthalic acid (0.12 mol), 4.3 kg of 1,3,5-benzenetricarboxylicacid (0.02 mol) and 163 g of an aqueous 50% (w/w) hypophosphorous acidsolution are successively introduced into the reactor. The reactor ispurged by a succession of 4 sequences of placing under vacuum andre-establishing atmospheric pressure with dry nitrogen.

The reaction mass is gradually heated from 20 to 260° C. with stirring,over about 200 minutes.

The reaction mass is gradually heated from 70 to 260° C. with stirring,over about 200 minutes.

After stirring for 30 minutes at 260° C., the reactor is graduallyplaced under vacuum over 60 minutes. The minimum vacuum is thenmaintained for a further 30 minutes. About 6 kg of distillate arecollected.

At the end of the cycle, a Sandvik palletting machine is connected tothe reactor outlet and the polymer is run out using a gear-type pump inrotary form. The pellets thus formed are then cooled on a metal beltcooled underneath with water. The polymer is bagged directly at the endof the belt. About 70 kg of polymer are collected per synthesis.

The hyperbranched copolyamide obtained is vitreous.

Example 7

Characterization of hyperbranched polyamides containing alkyl end groupswith different A-R—B₂/A-R′—B ratios and different molar masses

Various hyperbranched polymers are synthesized according to theprotocols described in Examples 1 to 4 and 6. In all cases, the monomerA-R′—B is ε-caprolactam and the monomer A-R—B₂ is 5-aminoisophthalicacid.

The contents of acid and amine end groups are assayed by potentiometry.The molar masses are determined by gel permeation chromatography (GPC)in dimethylacetamide, relative to polystyrene standards, and then by RIrefractometry.

The results are collated in Table I below. TABLE 1 Composition RatioTheoretical AEG CEG Mn Mw Mz No. BTC/AIPA/CL/C₁₆ or C₁₈ ARB₂/AR′B Mn(g/mol) (meq/Kg) (meq/Kg) (g/mol) (g/mol) (g/mol) IP 1 1/25/25/28 (C₁₆)1/1 13375 2.4 ± 0.6 20.4 ± 1.6 6020 11240 17830 1.87 2 1/6/6/9 (C₁₆) 1/13879 3.1 ± 0.3  7.7 ± 1.8 4890 7750 11440 1.58 3 1/20/40/23 (C₁₆) 1/213139 3.7 ± 0.4 35.7 ± 1.2 6780 13250 21600 1.95 4 1/5/10/8 (C₁₆) 1/23945 14.0 ± 0.5  15.5 ± 0.7 4860 7630 11280 1.57 6 1/6/6/0 (C₁₈) 1/14005 3.9 12.9 6600 11710 — 1.8Abbreviations:

-   -   BTC: Benzenetricarboxylic acid or trimesic acid    -   AIPA: 5-aminoisophthalic acid    -   CL: ε-caprolactam    -   C₁₆: n-Hexadecylamine    -   C₁₈: n-Octadecylamine    -   AEG; Content of amine end groups    -   CEG: Content of acid end groups    -   Mn, Mw, Mz: Mean molar masses in polystyrene equivalents    -   IP: Polydispersity index

The DSC analyses of these hyperbranched polyamides show only one broadmelting peak at about −4° C. This peak corresponds to the alkyl segmentsand underlines the phase microsegregation of the hydrophobic unitsrelative to the polyamide units.

Example 8

Preparation of mixtures of PA 6,6 polyamide matrix/glass fibre/C₁₆ alkylHBPA additive for modifying the rheological behaviour

The HBPAs of Examples 1, 2 and 3 are coarsely ground and preblended inthe desired proportions with PA 6,6 granules.

The PA 6,6 is defined as follows: viscosity index measured at 25° C. in90% formic acid (ISO 307) of 137, amine end group content of 53 meq/kgand acid end group content of 72 meq/kg.

Compositions containing 50% by weight of glass fibre (Owens CorningOCF180K) and a PA 6,6 matrix supplemented with variable amounts of theHBPAs of Examples 1, 2 and 3 are made by melt-blending at a temperatureof 280° C. in a twin-screw extruder.

A control consisting of a thermoplastic composition based on PA 6,6 and50% by weight of glass fibre is also prepared.

The rheological and mechanical properties of these compositions areevaluated in Example 14.

Example 9

Preparation of blends of PA 6,6 matrix+C₁₆ alkyl HBPA

The PA 6,6 used is the same as in Example 8 and the C₁-6 alkylated HBPBsare those of Examples 2 and 1, at weight contents of 5% and 10% (only10% for Example 1) relative to the total weight of the blend.

The rheological and mechanical evaluations are given in Example 14below.

Example 10

Preparation of a composition according to the invention based on PA6 andHBPA from Example 6

The HBPA from Example 6 is first preblended in the desired proportionswith PA 6 granules.

The PA 6 under consideration has a relative viscosity, measured at 25°C. at a concentration of 0.01 g/mg in 96% sulphuric acid solution, of2.7. Its amine end group content is 35 meq/kg and its acid end groupcontent is 57 meq/kg.

The compositions of PA 6 supplemented with variable amounts of HBPA fromExample 6 are produced by melt-blending at a temperature of 250° C. in atwin-screw extruder. A control PA 6 without HBPA is also prepared.

The rheological properties of these compositions are evaluated inExample 15.

Example 11

Preparation of a composition according to the invention based onhigh-mass PA 6 and HBPA from Example 6

The HBPA from Example 6 is first preblended in the desired proportionswith high-mass PA 6 granules.

The high-mass PA 6 is defined by its relative viscosity, measured at 25°C. at a concentration of 0.01 g/ml in 96% sulphuric acid solution, whichis greater than 3.5 and preferably greater than 3.8. Its amine end groupcontent is 33 meq/kg and its acid end group content is 31 meq/kg.

The compositions of high-mass PA 6 supplemented with variable amounts ofHBPA from Example 6 are produced by melt-blending at a temperature of300° C. in a twin-screw extruder. A high-mass PA 6 control without HBPAis also prepared.

The rheological properties of these compositions are evaluated inExample 15.

Example 12

Preparation of a composition according to the invention based onpolypropylene and HBPA from Example 6

The HPBA from Example 6 is first preblended in the desired proportionswith PP granules. The PP used is an Appryl® grade from Atofina, with aMelt Flow Index, measured at 230° C. under 2.16 kg, of 3 g/10 minutes(ISO 1133).

The compositions of PP supplemented with variable amounts of HBPA fromExample 6 are prepared by melt-blending at a temperature of 180° C. in atwin-screw extruder. A control PP without HBPA is also prepared.

The rheological properties of these compositions are evaluated inExample 16.

Example 13

Preparation of compositions based on PA 6,6 and functionalized Boltorn®(Perstorp) hyperbranched products

The incorporation of the hyperbranched products (at 5% by weightrelative to the total weight of the composition) into PA 6,6 isperformed by blending coarse powders, and then melt-blending using amicroextruder, at a temperature of 285° C.

The PA 6,6 under consideration has a viscosity index, measured at 25° C.in 90% formic acid (ISO 307) of 135 ml/g.

The Boltorn® hyperbranched products (polyester based) underconsideration are the following:

-   -   Boltorn® H30 functionalized with 95% benzoic acid    -   Boltorn® H40 functionalized with 95% dodecanoic acid.

The rheological properties of these compositions are evaluated inExample 17.

Example 14

Rheological and mechanical evaluation of the compositions of Examples 8and 9

The tests performed are:

-   -   Spiral test ST (melt flow index) for quantification of the flow        index of the compositions according to the invention and of the        control compositions:        The granules of composition M/hyperbranched polymer or of        control composition M are melted and then injected into a        spiral-shaped mould with a semicircular cross section 2 mm thick        and 4 mm in diameter, in a Demag H200-80 press at a plasticizing        cylinder temperature of 300° C., a mould temperature of 80° C.        and with an injection pressure of 1500 bar. The injection time        is 0.5 second. The result is expressed as the length of mould        correctly filled with the composition. The compositions        evaluated in this test all have an equivalent moisture content        before moulding to within 0.1% relative to the matrix.    -   Mechanical tests

The mechanical characteristics are evaluated by non-notched impact tests(ISO 179/1eU), notched impact tests (ISO 179/1eA), flexural modulus ISO178, flexural breaking stress ISO 178 and tests of temperature ofbending under load (HDT) ISO 75Ae. The results are given in Tables IIand III below. TABLE II Compositions with a 50% content of glass fibres(GF) Moisture % of change in Non-notched Notched Flexural Flexural HDT(° C.) Spiral content Mass of mass relative impact impact modulusbreaking stress (1.80 length before PA to the mass of (KJ/m²) (KJ/m²)(N/mm²) (N/mm²) N/mm²) Composition (mm) moulding (%) * (g/mol) ** thecontrol ISO 179/1Eu ISO 179/1eA ISO 178 ISO 178 ISO 75Ae Control 3390.20 65250 82.4 11.0 11800 280 248 PA66/50% GF PA66/50% GF + 363 0.1862440 −4.3 76.2 10.5 11500 268 245 2% HBPA/C₁₆ Ex. 1 PA66/50% GF + 3830.18 69830 +7.0 71.6 10.4 12100 270 248 5% HBPA/C₁₆ Ex. 1 PA66/50% GF +430 0.26 63550 −2.6 76.3 10.3 11500 262 245 2% HBPA/C₁₆ Ex. 2 PA66/50%GF + 512 0.20 63420 −2.8 75.9 10.0 10900 256 245 5% HBPA/C₁₆ Ex. 2PA66/50% GF + 399 0.24 62530 −4.2 74.5 10.2 11500 261 245 2% HBPA/C₁₆Ex. 3 PA66/50% GF + 440 0.18 64970 −0.4 67.9 10.1 11700 262 245 5%HBPA/C₁₆ Ex. 3* Moisture content relative to the matrix measured by the Karl-Fischermethod** Maximum of the molecular mass distribution of the polyamide matrixsupplemented with functionalized HBPA, as polystyrene equivalents,measured by Gel Permeation Chromatography (GPC) with refractometricdetection after carrying the spiral test for quantification of the flowindex.

TABLE III (Example 9) Compositions without glass fibre CompositionSpiral length (mm) PA66 556 PA66 + 5% HBPA/C₁₆ Ex. 2 588 PA66 + 10%HBPA/C₁₆ Ex. 2 988 PA66 + 10% HBPA/C₁₆ Ex. 2 866

Example 15

Evaluation of the flow index of the compositions of Examples 10 and 11

The results are given in Table IV below. TABLE IV Spiral Mass of the PAComposition length (mm) by GPC (g/mol) * Control PA 6 425 71560 PA 6 +5% HBPA 621 71400 Example 6 PA 6 + 10% HBPA 1033 70200 Example 6 Controlhigh-mass PA 6 355 82150 High-mass PA 6 + 5% HBPA 617 87740 Example 6* Maximum of the molecular mass distribution of the polyamide matrixsupplemented with functionalized HBPA, as polystyrene equivalents,measured by Gel Permeation Chromatography (GPC) with refractometricdetection after carrying the spiral test for quantification of the flowindex.

Example 16

Evaluation of the flow index of the compositions of Example 12

The results are given in Table V below TABLE V Composition Spiral Length(mm) Control PP 439 PP + 5% HBPA Example 6 516 PP + 10% HBPA Example 6715

Example 17

Evaluation of the flow index of the compositions of Example 13

A measurement of the force exerted on the screw axle by the moltenmaterial makes it possible to assess the flow index of the composition.

The relative reductions in force compared with the control PA 6,6without hyperbranched product and also the values of the mass of PA 6,6measured by GPC are collated in Table VI below. A comparative examplewith a composition PA 6,6+HBPA C₁₆ ₍1/25/25/28) is also mentioned inthis table. TABLE VI Variation in the Mass of PA by Compositionforce/control GPC (g/mol) * Control PA 6, 6  0 74000 PA 6, 6 + 5% HBPA−25% 74000 1/25/25/28 C₁₆ Example 1 PA 6, 6 + 5% Boltorn ® −47% 69000H30 functionalized with benzoic acid PA 6, 6 + 5% Boltorn ® −37% 68800H40 functionalized with dodecanoic acidMaximum of the molecular mass distribution of the polyamide matrixsupplemented with hyperbranched product, as polystyrene equivalents,measured by Gel Permeation Chromatography (GPC) with refractometricdetection after passing through a microextruder.

Example 18

Measurement of the values of the reductions in pack pressure (die head)during the spinning of the M/functionalized HBPA compositions ofExamples 2 and 4

-   -   The polyamide 66 used is a polyamide 66 comprising no titanium        dioxide, with a relative viscosity of 2.5 (measured at a        concentration of g/l in 96% sulphuric acid).    -   The incorporation of the HBPA (2% or 5% by weight relative to        the total weight of the composition) into the PA 66 is performed        by blending powders and then melt-blending using a twin-screw        extrusion device. The molten blend is then spun with a speed at        the first point of call of 800 m/minutes, so as to obtain a        continuous multifilament yarn of 90 dtex per 10 filaments.

The temperature-pressure and spinning course and the properties of theyarn obtained are detailed below:

-   -   Spinning course: no breaking    -   Twin-screw extruder heating: 285° C.    -   Spin speed of the screws: 120 rpm    -   Die head heating: 287° C.    -   Flow rate under die: 0.41 kg/h.

The multifilament or yarn consists of 10 strands (the die consists of 10holes) and the diameter of a strand is about 30 μm.

The values of the reductions in pack pressure (die head) are measuredusing a Dynisco probe pressure (0-350 bar).

The results obtained are given in Table VII below. TABLE VII Mass of PAby Pack GPC with pressure Delta detection by Composition (bar)pressure/control refractometer * Control PA 66 35.4 66 000 PA 66 + 5%25.5 −28.0% 67 000 1/5/10/8 Example 4 PA 66 + 5% 28.0 −20.9% 66 0001/6/6/9 Example 2 PA 66 + 2% 33.0 −6.8% 66 000 1/5/10/8 Example 4 PA66 + 2% 34.5 −2.5% 66 000 1/6/6/9 Example 2Maximum of the molecular mass distribution of the polyamide matrixsupplemented with functionalized HBPA, in polystyrene equivalents,measured by GPC with refractometric detection after spinning.

Example 19

Measurement of the reductions in pack pressure (die head) during thespinning of compositions based on high-mass PA 6 and HBPA of Example 6

-   -   The high-mass polyamide 6 used is the same as that described in        Example 11.    -   The introduction of the HBPA (2% or 5% by weight relative to the        total weight of the composition) into the high-mass PA 6 is        performed by blending powders and then melt-blending using a        twin-screw extrusion device. The molten blend is then spun with        a speed at the first point of call of 800 m/minute, so as to        obtain a continuous multifilament yarn of 220 dtex per 10        filaments. The temperature, pressure and spinning course and the        properties of the yarns obtained are detailed below:        -   Spinning course: no breaking        -   Twin-screw extruder heating: 325° C.        -   Screw spin speed: 220 rpm        -   Die head heating: 296° C.

The values of the reductions in pack pressure (die head) are measuredusing a Dynisco probe pressure (0-350 bar).

The results obtained are given in Table VIII below. TABLE VIII Pack Massof PA pressure Delta by GPC Composition (bar) pressure/control (g/mol) *Control PA 6 118  0 82360 High mass PA 6 + 100 −15% 81720 2% HBPAExample 11 High mass PA 6 + 70 −41% 86280 5% HBPA Example 11Maximum of the molecular mass distribution of the polyamide matrixsupplemented with functionalized HBPA, in polystyrene equivalents,measured by GPC with refractometric detection after spinning.

Example 20

Comparison of the molar mass of the matrices of compositions accordingto the invention (PA 66/C₁₆ alkyl HBPA/glass fibre) of the type of thoseof Example 8 and of compositions comprising polyamide 66, an additive ofthe unfunctionalized HPBA type and glass fibre.

20.1—Preparation of the unfunctionalized HBPA:

Synthesis of a hyperbranched copolyamide containing carboxylic acid endgroups by melt-copolycondensation of 1,3,5-benzenetricarboxylic acid(core molecule of R¹—B″₃ type, with B″═COOH); of 5-aminoisophthalic acid(branching molecule of A-R—B₂ type, with A═NH₂ and B=COOH) and ofε-caprolactam (spacer of A′-R′—B′ type with A′═NH₂ and B′═COOH).

The reaction is performed at atmospheric pressure in a 7.5 l autoclavecommonly used for the molten-phase synthesis of polyesters orpolyamides.

The monomers are completely loaded at the start of the test. 1811.5 g of5-aminoisophthalic acid (10 mol), 84 g of 1,3,5-benzenetricarboxylicacid (0.4 mol), 1131.6 g of ε-caprolactam (10 mol), and 1.35 g of anaqueous 50% (w/w) hypophosphorous acid solution are successivelyintroduced into the reactor. The reactor is purged by a succession of 4sequences of placing under vacuum and of re-establishing atmosphericpressure with dry nitrogen.

The reaction mass is gradually heated from 20 to 200° C. over 100minutes, and then from 200 to 245° C. over 60 minutes. When the bulktemperature reaches 100° C., stirring is started at a spin speed of 50rpm. The distillation begins at a bulk temperature of 160° C. andcontinues up to a temperature of 243° C. At 245° C., the stirring isstopped and the reactor is placed under an excess pressure of nitrogen.Next, the base valve is gradually opened and the polymer is run out intoa stainless-steel bucket filled with water.

The water contained in the 221.06 g of collected distillate is titratedusing a Karl Fischer coulometer. The water content of the distillate is81.1%, which reflects an overall degree of progress of 99.3%.

The hyperbranched copolyamide obtained is soluble at room temperature inthe amount of aqueous sodium hydroxide required to neutralize theterminal acid functions.

20.2—Preparation of the compositions PA 66+functionalized HBPA accordingto 20.1+glass fibre and of a control composition free ofunfunctionalized HBPA

The process is performed as indicated in Example 8, with the exceptionof the extrusion temperature, which in this case is 250° C.

20.3—Measurement of the molar mass of the matrix of the compositionsaccording to 20.2 and of the compositions obtained in Example 8,according to protocol P

The compositions and the results are given in Table IX below. TABLE IX(Example 20) Comparison between unfunctionalized HBPA (COOH end group)and functionalized HBPA (alkyl end group) on granules of blend with PA(obtained from extrusion) Mass of PA % variation in Composition of(g/mol) according mass relative to the granules to protocol P thecontrol Control 73770 / PA 66/50% GF PA 66/50% GF + 73690 −0.1 2%HBPA/C₁₆ Ex. 1 PA 66/50% GF + 74320 +0.7 5% HBPA/C₁₆ Ex. 1 PA 66/50%GF + 75020 +1.7 2% HBPA/C₁₆ Ex. 2 PA 66/50% GF + 75650 +2.4 5% HBPA/C₁₆Ex. 2 PA 66/50% GF + 74780 +1.4 2% HBPA/C₁₆ Ex. 3 PA 66/50% GF + 75330+2.1 5% HBPA/C₁₆ Ex. 3 Control 75000 / PA 6/50% GF according to 20.2 PA6/50% GF + 70000 −6.6 2% HBPA/COOH according to 20.2 PA 6/50% GF + 60000−20 5% HBPA/COOH according to 20.2 PA 6/50% GF + 57000 −24 10% HBPA/COOHaccording to 20.2

1-23. (canceled)
 24. A thermoplastic polymer composition, comprising: amatrix M based on at least one thermoplastic polymer, and at least onehyperbranched polymer additive for modifying the rheological behaviour,comprising at least one polymer: which is functionalized, which ishyperbranched, at least 50% of the end groups of this hyperbranchedpolymer are functionalized with R², R² being a substituted orunsubstituted hydrocarbon-based radical of the silicone, linear orbranched alkyl, aromatic, arylalkyl, alkylaryl or cycloaliphatic,optionally having one or more unsaturations or one or more hetero atoms.25. A composition according to claim 24, wherein the hyperbranchedpolymer is a polyester, polyesteramide or a polyamide.
 26. A compositionaccording to claim 24, wherein the hyperbranched polymer additive is ahyperbranched polyamide comprising at least one hyperbranchedcopolyamide obtained by reaction between: at least one monomer offormula (I) below:A-R—B_(f) in which A is a polymerization-reactive function of a firsttype, B is a polymerization-reactive function of a second type that iscapable of reacting with A, R is a hydrocarbon-based species optionallycomprising hetero atoms, and f is the total number of reactive functionsB per monomer with f≧2; optionally at least one difunctional spacermonomer of formula (II) below:A′-R′—B′ or the corresponding lactams, wherein A′, B′ and R′ have thesame meaning as that given above for A, B and R, respectively in formula(I); optionally at least one “core” monomer of formula (III):R¹ (B″)_(n) whrein: R¹ is a substituted or unsubstitutedhydrocarbon-based radical of the silicone, linear or branched alkyl,aromatic, alkylaryl, arylalkyl or cycloaliphatic type which may compriseunsaturations and/or hetero atoms; B″ is a reactive function of the samenature as B or B′; and n≧1; and at least one “chain-limiting”functionalization monomer corresponding to formula (IV):R²-A″ wherein: A″ is a reactive function of the same nature as A or A′.27. A composition according to claim 26, wherein, 2≦f≦10 and 1≦n≦100 28.A composition according to claim 24, wherein it is free of hyperbranchedpolymer additives, resulting in a reduction of the molar mass of thematrix M of greater than or equal to 7% relative to a controlcomposition comprising the same matrix M not supplemented withhyperbranched polymer, the molar mass measurement being performedaccording to a given protocol P.
 29. A composition according to claim28, wherein the molar mass measurement is performed on the compositionto be analysed and on the control composition, which are extruded,solidified and then formed into granules.
 30. A composition according toclaim 28, wherein the molar mass measurement is performed on thecomposition to be analysed and on the control composition, which areextruded, solidified, formed into granules and then subjected to a giventest Qf for quantification of their flow index.
 31. A compositionaccording to claim 27, wherein, in the hyperbranched copolyamideconstituting the hyperbranched polymer additive: the hydrocarbon-basedspecies R and R′ of the monomers (I) and (II) respectively, eachcomprise: i. at least one linear or branched aliphatic radical; ii. atleast one cycloaliphatic radical; iii. at least one aromatic radicalcomprising one or more aromatic nuclei; or iv. at least onearylaliphatic radical; these radicals (i), (ii), (iii) and (iv) possiblybeing substituted or comprising hetero atoms; A or A′ is a reactivefunction being amine, amine salt, acid, ester, acid halide or amide; andB or B′ is a reactive function being acid, ester, acid halide, amide,amine or amine.
 32. A composition according to claim 26, wherein thepolymerization-reactive functions A, B, A′ and B′ of the hyperbranchedcopolyamide are carboxylic or amine functions.
 33. A compositionaccording to claim 26, wherein the hyperbranched copolyamide (HBPA)comprises monomers (III) in a III/I+II+IV molar ratio defined asfollows: III/I+II+IV≦1/150.
 34. A composition according to claim 26,wherein the monomer of formula (I) of the hyperbranched copolyamide(HBPA) is a compound in which A represents the amine function, Brepresents the carboxylic function, R represents an aromatic radical,and f=2.
 35. A composition according to claim 26, wherein, as regardsthe hyperbranched copolyamide (HBPA): the monomer (I) is:5-amino-isophthalic acid, 6-amino-undecanedioic acid, 3-aminopimelicdiacid, aspartic acid, 3,5-diaminobenzoic acid, or 3,4-diaminobenzoicacid; the difunctional monomer of formula (II) is: ε-caprolactam or thecorresponding amino acid, aminocaproic acid, para- or meta-aminobenzoicacid, 11-amino-undecanoic acid, lauryllactam and/or the correspondingamino acid, or 12-aminododecanoic acid; the “core” monomer (III) is:1,3,5-benzenetricarboxylic acid,2,2,6,6-tetra(β-carboxyethyl)cyclohexanone, 2,4,6-tri(aminocaproicacid)-1,3,5-triazine, or 4-aminoethyl-1,8-octanediamine; and the“chain-limiting” functionalization monomer (IV) is: n-hexadecylamine,n-octadecylamine, n-dodecylamine, benzylamine.
 36. A compositionaccording to claim 24, wherein the thermoplastic (co)polymer(s)constituting the matrix is (are) polyolefins, polyesters, polyalkyleneoxides, polyoxyalkylenes, polyhalogenoalkylenes,poly(alkylene-phthalates or terephthalates), poly(phenyl or phenylenes),poly(phenylene oxide or sulphide), polyvinyl acetates, polyvinylalcohols, polyvinyl halides, polyvinylidene halides, polyvinyl nitriles,polyamides, polyimides, polycarbonates, polysiloxanes, acrylic ormethacrylic acid polymers, polyacrylates or polymethacrylates, naturalpolymers, cellulose, cellulose derivatives, synthetic polymers,synthetic elastomers, thermoplastic copolymers comprising at least onemonomer that is identical to any of the monomers included in theabovementioned polymers, blends oralloys of all these (co)polymers. 37.A composition according to claim 36, wherein the thermoplasticpolymer(s) is (are) nylon 6, nylon 6,6, nylon 4, nylon 11, nylon 12,polyamides 4-6, 6-10, 6-12, 6-36, or 12-12.
 38. A composition accordingto claim 37, wherein the thermoplastic polymer(s) is (are) a polyamide6, whose relative viscosity, measured at 25° C. at a concentration of0.01 g/ml in a 96% sulphuric acid solution, is greater than 3.5.
 39. Acomposition according to claim 37, wherein the thermoplastic polymer(s)is (are) a polyamide 6,6.
 40. A composition according to claim 24,wherein the additive comprising the hyperbranched copolymer is presentin a proportion (expressed as % by dry weight relative to the total massof the composition) of 0.1 to
 50. 41. A composition according to claim26, wherein the additive comprising the hyperbranched copolymer has acontent of acid or amine end groups (EG) (expressed in meq/kg) ofbetween 0 and
 25. 42. A composition according to claim 24, wherein theradicals R² are the same throughout the hyperbranched polymer.
 43. Acomposition according to claim 24, further comprising at least onereinforcing filler or bulking filler being fibrous fillers, glass fiber,mineral fillers, fillers made of thermosetting material, powder fillersor talc.
 44. Articles obtained by forming a composition as defined inclaim
 24. 45. Articles according to claim 44, wherein the forming ismoulding the composition.
 46. Articles according to claim 44, beingyarns, fibers, films or filaments.